Using new serialization module

[sdelamo]

I would like for us to use the new serialization module in every guide. It will involve adding the serialization feature to every guide and start annotating POJOs with @Serdeable when necessary. And explaning the user what does the Serdeable annotation does.

@alvarosanchez @burtbeckwith @graemerocher @shingjo thoughts?

[graemerocher]

sounds good, but maybe it should be GA before we merge it into all guides

[sdelamo]

Agree.

However, I think we should test it to see if we find anything before GA.